Scrub the potatoes thoroughly, but do not peel. Slice one very thin layer off each potato, along the length, then set aside. This serves as a solid base to rest on while you slice them. Place a potato flat side-down and use a sharp knife to make slices that are about 1/8-inch apart; slice into the potato but not completely through it — the slices should stay connected at the bottom.

Our preferred way to keep the potato intact but evenly sliced is to run a metal skewer through the lower third of the potato lengthwise. This allows you make perfect slices without cutting all the way through.

Using a pastry brush, brush the bottom and sides of a cast iron skillet and each potato with the butter. Brush the potatoes generously reserving some butter for basting during cooking. Place potatoes in skillet Sprinkle with salt and pepper.

Bake for 60 minutes — basting the potatoes every 15 minutes or so with the remaining butter. If using the grated cheese, sprinkle on the potatoes and cook an additional 15 minutes or until completely done and golden brown on top.